msem-instigator

You may exert Accursed Bear as it attacks. When you do, it gets +1/+0 and gains trample until end of turn. (An exerted creature won't untap during your next untap step.)

Flying
{2}{W}, Exile a non-Spirit creature card from your graveyard: Create a 1/1 white Spirit creature token with flying.

Target player mills X cards, where X is the number of cards in your graveyard.
Flashback {3}{U/B}{U/B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Non-Human creatures you control get +1/+0.

{T}, Pay 1 life: Surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)
At the beginning of your end step, if your life total is less than 5, sacrifice Achet-Aton's Vizier. If you do, create a 4/4 black Demon creature token with flying.

As an additional cost to cast Acid Sewage, reappropriate or pay {3}. (To reappropriate, exile exactly two cards from your hand and/or graveyard.)
Destroy target creature.

This spell costs {2} less to cast if you've cast both an instant spell and a sorcery spell this turn.
Haste

When Acolyte of Griselbrand dies, you draw a card and you lose 1 life.
Foreshadow {4}{B} (You may cast this spell for its foreshadow cost. If you do, also trigger its “dies” abilities when it enters.)

When Acolyte of Night dies, each opponent loses 1 life.

Flying, lifelink, deathtouch

{T}: Untap target land.
{4}{G}: This creature gets +3/+3 until end of turn.

Death knell — Each opponent loses 1 life. You gain life equal to the amount of life lost this way. (As a creature you control dies, trigger one death knell of that creature or another permanent you control.)
Whenever a creature dies, trigger a death knell of a permanent you control.

Choose two —
• Untap target nonland permanent.
• Target creature gets +2/+0 until end of turn.
• Target creature gains hexproof until end of turn.

Return target nonland permanent to its owner's hand.
Amass Soldiers 1. (Put a +1/+1 counter on an Army you control. It's also a Soldier. If you don't control one, create an 0/0 black Soldier Army creature token first.)

Flash
Flying, first strike, lifelink

Creatures your opponents control get -1/-0.

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.
Draw a card.

Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
Menagerie — If there are five or more creature types among creatures you control, creatures you control get +1/+1 until end of turn.

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn.
Agonize (You may cast this card from your graveyard by putting a -1/-1 counter on a creature you control in addition to paying its other costs. Then exile this card.)

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. (If you exert it, it will still untap for other players.)

Target instant or sorcery spell gains “This spell deals 4 damage to you.”

Revive {3}{G} ({3}{G}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

When Adamant Healer enters, you may move any number of counters from target creature onto another target creature with the same controller.

Whenever a -1/-1 counter is put on a creature, you may create a 1/1 green Elf Druid creature token.

Lifelink
Converge — When Adapted Explorer enters, it deals X damage to up to one target tapped creature, where X is the number of colors of mana spent to cast it.